Apparatus for printing on two surfaces of an article



March 9, 1965 L. w. FREEMAN APPARATUS FOR PRINTING ON TWO SURFACES OF ANARTICLE 3 sheets sheet 1 Filed Jan. 7, 1963 |NvErsi1ToR FREEMAN BYATTORNEYS LAWRENCE W- March 9, 1965 L. w. FREEMAN 3,172,355

APPARATUS FOR PRINTING ON TWO SURFACES OF AN ARTICLE Filed Jan. 7, 19632/4 3 Sheets-Sheet 2 LAWRENCE w. F'REEMAI}! wwflpmggww'cdwaiyw Y BATTORNEYS March 9, 1965 w. FREEMAN 3,172,355

APPARATUS FOR PRINTING on TWO suamcss OF AN mmcw I INVENTOR LAWRENCE WFREEMAN gawu, QM; @JQM pm ATTORNEYS United States Patent 3,172,355APPARATUS FOR PRINTING ON TWO SURFACES OF AN ARTICLE Lawrence W.Freeman, West Hartford, Conn., assignor to Monsanto Company, acorporation of Delaware Filed Jan. 7, 1963, Ser. No. 249,879 27 Claims.(Cl. 101-119) This invention pertains to mechanisms for handling andforming indicia on articles. Specifically it relates to a silk screenprinting mechanism including two, rotatable silk screen printing devicesand associated conveying means by means of which a plurality of articlesmay be consecutively fed through the apparatus and be automaticallyprinted on two diametrically opposite surfaces.

Modern, high speed, automatic printing operations impose exactingrequirements on printing apparatus. Printing mechanisms, in order to beeffectively competitive in the present market, must be capable of highspeed ac curate printing operations with minimum structural complexity.It has become increasingly desirable for mechanisms to be capable ofhandling non-circular articles such as conventional, blow molded plasticbottles having a generally oval shaped cross section and to be capableof printing indicia on oppositely disposed arcuate surfaces of sucharticles.

Printing mechanisms heretofore developed have been characterized bysubstantial disadvantages, foremost among which has been unduestructural complexity. Particular difliculty has been involved withrotatable drum types of silk screen printing mechanisms in effecting thedistribution of ink upon peripherally carried silk screen surfaces. Inkdistributors in such mechanisms are normally located Within the druminterior. Heretofore such distributors have either undesirably engagedscreen supporting frame members during the rotation of the printingdrums or have been mounted for cyclic reciprocation toward and away fromthe printing portions of the silk screens. As will be appreciated,contact between the distributor and frame members entails severe wear ofthe distributing member with the likelihood of damage or failureoccurring. Cyclic reciprocation of the distributor involves thecomplexity associated with cycling control means.

Additional disadvantages involved with prior art, rotatable drum typesof silk screen mechanisms pertain to the correlating of the operation ofmechanisms for conveying articles toward and away from the printingdrums with the operation of the drums themselves.

Other problems have related to a general inability to obtain access toink distributing members while silk screen drums are rotating so as toeffect suitable apparatus adjustment or corrections.

Further problems associated with prior art printing structures haveinvolved the handling of articles on conveyors adapted to feed sucharticles toward and away from printing mechanisms and in providingreliable yet structurally simple mechanisms for changing the position ofarticles after they have been printed on one surface so as to besuitably and accurately registered to receive indicia on anothersurface.

Yet another difficulty of prior art structures has involved thedistribution of ink on silk screen printing surfaces. In general, priorart distributors have effected a uniform distribution of ink across asilk screen pattern. Such a uniform distribution has not taken intoaccount the varying requirements of printing patterns along the axis ofthe distribution outlet such that excessive accumulation of unused inkhas tended to occur in localized pattern areas having minimum inkdemands.

In recognition of the need for an improved article handling and indiciaforming system, it is an object of this 3,172,355 Patented Mar. 9, 1965invention to provide such a system which is particularly adapted to silkscreen printing techniques and by means of which the aforenoted priorart disadvantages, may be substantially obviated.

It is a particular object of the invention to provide a rotatable drumtype of silk screen printing unit, including an internally disposed inkdistributing member which re-' mains stationary throughout a continuous,multiple article printing operation and yet which does not engage frameor silk screen supporting members of the printing drum while the drum isrotating.

Yet another object of the invention is to provide such an indiciaforming apparatus which affords continuous access to the inkdistributing member while a printing plate bearing drum is rotating.

A further object of the invention is to provide such a mechanism,including an ink distributor which is adapted to distribute printing inkin accordance with localized printing requirements of a printingpattern.

An additional object of the invention is to provide a piston andcylinder assembly type of ink distributing structure which is uniquelyconfigured such that the assembly may be positioned in close proximityto silk screen printing surfaces to effect the transfer of ink to silkscreen surfaces without having other portions of the assembly engage thesilk screen surfaces or frame members of a screen supporting drum.

It is also an object of the invention to provide a print-v ing mechanismwhich enables the forming of indicia on two separate surfaces of anarticle in an automatic and expeditious fashion with a minimum ofstructural complexity. In accomplishing this objective, means are alsofprovided for forming indicia on articles of non-circular cross-sectionssuch as generally oval shaped bottles.

A still further object of the invention is to provide a mechanism forrigidly supporting articles such as oval shaped bottles on an endlessconveyor so as to eifect tangential, indicia forming contact between thearticles and a rotary printing surface. 7

It is an additional object of the invention to provide article handlingmechanisms including multiple, endless conveyor flights and havingdevices for effecting the simultaneous release of articles from multipleflights and the simultaneous release of articles from article. holderson one flight and the simultaneous placing of article holders on anotherflight in a condition to receive articles released from the one flight.

Still another object of the invention is to provide an article handlingmechanism including article holders uniquely adapted for use withendless conveyors and which effect automatic and accurate positioning ofarticles for multiple indicia forming operations. Uniquely com binedwith such holders is a device for detecting the absence of articles tobe printed.

In partially accomplishing the objects of this invention there isprovided an indicia forming mechanism including a pair of annular rims,which rims are coaxial and spaced along their common axis. A pluralityof frame members extend between and are connected to these annular rims.Means are provided for rotatably supporting the interconnected annularrims and for rotating the interconnected rims about their common axis. Aplurality of indicia forming plates extend between the rims with eachsuch plate having a portion thereof curved in an are having a radiusextending from the common axis A of the rims. Support means are providedfor each indicia forming plate, which support means have portions ex-'members. The fluid distributing means is positioned'so as to engage thecurved portions of the indicia forming plates yet be spaced from thetangentially extending portions of the support means as the annular rimsare rotated about their common axis.

The fluid distributing means desirably comprises a piston and cylinderassembly including a sloping cylinder head extending from an elongatefluid outlet. The sloping cylinder head facilitates the positioning ofthe assembly in close proximity to the indicia forming plates withoutcausing structural interference between the assembly and framecomponents of the mechanism during the rotation of the annular rims. Itis also desirable that the cylinder be provided with a uniquedistributing member adjacent its outlet so as to control the expulsionof fluid from the assembly in accordance with the varying demands of apattern along the axis of the elongate cylinder outlet.

With respect to the forming of indicia on two surfaces of an article,there is contemplated an apparatus which includes first indicia formingmeans associated with first article conveying means adapted to conveyarticles toward and away from the first indicia forming means. Secondindicia forming means are provided which are spaced from the firstindicia forming means. Second article conveying means are included whichare adapted to convey articles toward and away from the second indiciaforming means. The first article conveying means has a first horizontalflight extending away from the first indicia forming means while thesecond article conveying means has a second horizontal flight leading tothe second indicia forming means and disposed beneath and in spacedrelation with the first horizontal flight. Means are provided forreleasing articles from the first horizontal flight which have beenprinted on one surface so that they may fall by gravity onto the secondhorizontal flight to be carried to the second indicia forming means toreceive indicia on a second surface.

Also envisioned as important features of the invention is a uniquearticle holder particularly adapted for use with an endless conveyorwhere an article is to be transferred from one conveyor flight toanother to effect accurate registered printing on multiple articlesurfaces. Each such article holder has a concave portion to support anarticle side, an abutment to engage one article end, and a pivoted jawadapted to resiliently engage the other article e'nd. Aycam follower iscarried by the pivoted jaw and is adapted to engage stationary abutmenttype cams to effect the pivoting of the jaw from article engaging toarticle receiving positions.

In order to effect tangential indicia forming contact between endlessconveyor carried articles and printing surfaces carried by the peripheryof a rotatable printing drum, the article holders are rigidly attachedto their associated endless conveyors so as to support articles withtheir median planes extending from their longitudinal axis radially toarcuate article surfaces to receive indicia and are perpendicular to theportions of the endless conveyors which they intersect. Holders thusmounted may be carried around suitably diametered rollers locatedadjacent rotatable printing drums to effect tangential indicia formingcontact between the article surfaces to be printed andindicia formingmeans carried by the drum. Desirably, each endless conveyor is of thesprocket chain type and is engaged with toothed peripheral portions ofits associated printing drum so as to effect rotation of the drum whichis positively coordinated with the speed of the conveyor.

'In describing the invention reference will be made to preferredembodiments of the mechanism as illustrated in the accompanyingdrawings. In these drawings:

FIG. 1 is a schematic, side elevational view of a complete mechanismincluding two rotatable, silk screen printing units, each having anassociated endless conveyor. The conveyors and silk screen printingunits are interrelated so as toreffect. the: automatic formingofindiciaon.

two surfaces of each article passing through the mechanism;

FIG. 2 is a transverse, partially sectioned and broken away view of oneof the two silk screen mechanisms shown in FIG. 1;

FIG. 3 is a sectional view of the silk screen printing mechanism of FIG.2 taken along the section line 3-3;

FIG. 4 is a plan view of a representative silk screen and silk screenframe adapted to be mounted upon the FIG. 2 mechanism;

FIG. 5 is an enlarged representation of a portion of FIG. 1 apparatusillustrating an article holder and a mechanism for changing the holderfrom article holding to article receiving conditions;

FIG. 6 is a sectional view of an article holder portion shown in FIG. 5as taken along the section line 66.

FIG. 7 is a fragmentary, partially sectional view of a pivoted jawcomponent of the article holder illustrated in FIG. 8 is a fragmentary,sectional view of an adjustment portion of a pivoted jaw actuatingmechanism shown in the FIG. 5 illustration as viewed along the sectionline 8-8;

FIG. 9 is a fragmentary, and enlarged view of the manner in which theendless chain conveyors of the FIG. 1 mechanism are employed to effectthe coordinated rotation of the silk screen printing drums shown in FIG.1;

FIG. 10 is a fragmentary, sectional view of the FIG. 9 apparatus asviewed along the section line 1010;

FIG. 11 is an enlarged and sectioned view of the ink distributorassembly incorporated in each silk screen printing mechanism of the FIG.1 apparatus; and

FIG. 12 is a fragmentary, end view of the ink distributor assembly shownin FIG. 11 as viewed along the view line 1212.

FIG. 1 schematically illustrates an overall mechanism for accomplishingautomatic silk screen printing on oppositely disposed, arcuate faces ofarticles such as plastic bottles having a generally oval shapedcross-section.

As shown in FIG. 1, the mechanism includes a first, rotary drum typeprinting unit 1 adapted to print one article face and a second, rotarydrum type of silk screen printing unit 2 adapted to print a secondarticle face. As shown in FIG. 1, silk screen printing units 1 and 2 arepreferably both laterally and vertically spaced from each other.

A first endless conveyor 3 schematically illustrated in phantom line inFIG. 1, conveys articles to the first printing unit 1 along an upper,horizontally disposed flight 3a and carries articles which have beenprinted on one face away from the printing unit 1 along a lowerhorizontal flight 3b. A second endless conveyor 4, shown schematicallyin dotted line, is associated with the second rotary screen printingunit 2. Endless conveyor 4 is positioned beneath endless conveyor 3 andincludes an upper horizontal flight 4a positioned beneath the lowerhorizontal flight 3b of conveyor 3, which upper flight 4a is adapted toconvey articles toward printing unit 2 to receive printed indicia on asecond face. Conveyor 4 includes a lower horizontal conveyor flight 4bfor transporting articles generally away from printing unit 2.

In FIG. 1 printing unit 1 and the conveyor 3 are shown schematicallywith the supporting frame merely being indicated in phantom lines. Theadditional structural dctail shown in connection with the conveyor 4,the printing. unit 2 and the frame and structure associated with thesecomponents provides clarification of details of the system to bedescribed hereinafter.

At the transfer station indicated in FIG. 1, conventional articletransfer means may be provided for loading articles to be printed uponthe conveyor 3. Conveying means such as an endless conveyor 5 disposedbeneath the flight 4b may be employed to transport articles which havebeen printed on two separate faces away from the printing mechanism.Endless. conveyor 5 may be provided with a plurality of cradle type,article receiving holders a.

In operation of the mechanism shown in FIG. 1, unprinted articles arecarried from horizontal flight 3a to the printing unit 1. At this unit,such articles are supported on the conveyor 3 so that a first surface toreceive indicia is moved in tangential, indicia forming contact with asilk screen carried by the rotary printing unit. The article with onesurface printed is then carried away from the printing unit 1 and, as itmoves along the lower flight 3b, is discharged from the conveyor 3 sothat it falls by gravity on to the upper flight 4a of the conveyor 4. Asshown in FIG. 1, flights 3b and 4a are relatively closely spaced.Because of this close spacing, there is little or no possibility ofarticle reorientation occuring as the article falls by gravity from theconveyor flight 3b onto the conveyor flight 4a. Thus, in making thetransfer from the flight 3b the flight 4a, an article is repositioned inrelation to its supporting conveyor so that the unprinted article facewhich was disposed inwardly on conveyor 3 is disposed outwardly on theconveyor 4. The article is then carried by the conveyor 4 to the secondsilk screen, rotary printing unit 2 where the second article face isprinted in the same manner in which the first face was printed by theprinting unit 1.

Rotary printing unit 1 and rotary printing unit 2 are substantiallyidentical rotary silk screen printing units arranged in oppositelyoriented relationship, as shown in FIG. 1, so as to rotate in oppositedirections.

In describing the structure of each rotary printing unit, the rotaryunit 2 shown in full line in FIG. 1 will be referred to as typifying thestructure of both printing units.

FIGS. 2 and 3 disclose the structural details of the rotary printingunit 2. FIG. 2 provides a partially sectioned, end elevational view ofthe printer unit 2. FIG. 3 provides a sectional, fragmentary, sideelevational view of the unit 2.

As shown in FIG. 3, the rotary printing unit 2 includes a first,generally annular rim 6 disposed on one side of the printing unit and asecond, generally annular rim 7 disposed on the other side of the unit.Rims 6 and 7 are coaxial and spaced along the axis of rotation of theprinting unit, which axis of rotation is the common axis of the rims 6and 7. A plurality of mounting members 8 shown in FIG. 2 may be fastenedto rim members 6 and 7 by conventional fastening means such as threadedbolts 9. Rim 6 is rotatably supported by an annular, i.e. cylindricalsection, type of support member 10 while annular rim 7 is similarlysupported by an annular, cylindrical section type support member 11. Rim6 includes a central aperture 12, of circular, cross section, throughwhich the support member 10 projects. Support member 10 is journaled inaperture 12 by means of a conventional roller bearing assembly 13. Rim 7includes a similar, centrally disposed circular aperture 14. Annularsupport member 11 is journaled in aperture 14 by means of a conventionalroller bearing assembly 15.

Annular support member 10 includes a central opening 16 which, incooperation with aperture 12, affords direct access to the printing unitinterior, even while the unit is rotating. Similarly, support member 11includes a central opening 17 alfording direct access to the printingunit interior, while the unit is rotating.

The printing unit 2 is rotated by interengagement of the conveyor 4 withsprocket toothed rims 18 and 19 mounted respectively on annular rims 6and 7 in a manner to be hereinafter described. The sprocket toothed rim18 and 19 shown in FIGS. 2 and 3 are not illustrated in FIG. 1 in orderto simplify the illustration of the overall system.

An ink distributing assembly 20 is positioned between the rims 6 and 7and within the path of rotation traversed by the frame members 8.

Printing unit 2 supports a plurality of indicia forming assemblies 21which extends between the rims 6 and 7.

As shown in FIG. 4, a representative assembly 21 includes a generallyrectangular, silk screen surface, printing place 21a mounted on arectangular supporting frame 21!; fabricated of resilient metal or othermaterial. Referring to FIG. 2, ,it will be seen that each printingassembly 21 is mounted so as to have an intermediate portion curved inan arc having a radius extending from the axis of rotation of theprinting unit. End portions of the silk screen printing surface 21aextend tangentially away from the intermediate curved portion.Similarly, the frame 21b, which supports the silk screen plate 21a, hasa mid portion, i. e. the mid portions of its slides, which are curved inan arc conforming generally to the arc of the mid portion of the plate21a while its end portions extend tangentially away therefrom.

Silk screen and frame assemblies are supported on the printing unit 2 inthe manner shown in FIGS. 2 and 3. The slides of each frame 21b aresupported by portions of the rims 6 and 7, which rims are shaped toconform to the curved and tangentially extending configuration desiredfor the screen and plate assembly. Each end of the silk screen and frameassembly 21 is secured by a holding member 22. Holding members 22 areattached to mounting members 8 by conventional fastening means such asthreaded fasteners 23. One side of each holder 22 includes a slot 22aextending along the length of the end of a silk screen frame 21 and isadapted to receive and retain this frame end. Another slot 22b otherside of the holder 22 and is adapted to receive and retain the end ofthe tangentially extending end portion of another, adjacent silk screenframe.

As will be appreciated, the holding members 22, in being connected tomounting member 8 on rims 6 and 7 and extending along the length of theend of the screen frames 21, may also be considered to be frame membersextending transversely between the interconnected rims 6 and 7.

As will be appreciated, each frame and silk screen assembly 21 may bemounted upon the periphery of the printing unit 2 merely by flexing themid portion of the assembly to allow its outer ends to slip into theslots of a pair of adjacent assembly holders 22. When the assembly isreleased, the resilience of the frame 21b will effectively draw theframe into snug engagement with the rims 6 and 7 and cause the frameends to extend into locked position within the slots 22a and 22b ofadjacent holders 22. Accurate registration of the assembly 21 on theprinting unit 2 may be assured by means of registration pins 24 carriedby the rims 6 and 7 adopted to engage registration notches 25 formed onthe sides of frame 21b.

In order to accommodate to particular article requirements, it may benecessary to adjust the position of each printing unit toward and awayfrom its associated conveyor. One such mechanism for adjusting theposition of a printing unit transversely of its axis of rotation isshown in FIGS. 2 and 3. This adjusting mechanism includes a pair offrame mounted rails 26 and 27 adapted to slideably support upper andlower flattened peripheral surfaces of the annular support member 16 anda pair of frame supported rail members 28 and 29 adapted to slideablysupport upper and lower flattened, peripheral surfaces of the annularsupport member 11. A horizontally aligned toothed rack 30 is mounted onthe annular support member 10 while another horizontally aligned toothedrack 31 is mounted on the annular support member 11. A pinion assemblyincluding a first pinion gear 32 meshingly engaged with the toothed rack30 and a second pinion gear 33 meshingly engaged with the toothed rack31 is mounted upon an actuating rod 34 which is journaled in the frameassembly and provided with a manually operated turning handle 35. Whenthe handle 35 is rotated so as to rotate the pinion gears 32 and 33, theprinting unit 2 is caused to move along the axis of the racks 30 and 31so as to be displaced transversely of the axis of rotation of the rims 6and 7. In this manner the position of each printing unit in relation toits associated conveyor may be expeditiously and effectively adjusted toobtain the desired Contact between conveyor carried articles and thesilk. screen printing surfaces.

When each ink distributor assembly is positioned in operative position,as shown in FIGS. 1 and 2, the ink distributing end a of each assemblyis positioned so as to engage the curved portions of the silk screens21a rotatably carried by the rims 6 and 7 past this distributing end20a. The distributor 20 is positioned and configured so as to be spacedfrom tangentially extending portions of the silk screen 21a and the silkscreen frames 21b as well as the mounting members 8 and the framemembers 22 while these components are rotated past the ink distributingend 20a of the distributor assembly 20.

The structural details of the ink distributing assembly 20 are shown inFIGS. 2, 3, 11, and 12.

As shown in FIG. 2, each assembly 20 includes a cylinder 36 whichdefines an ink reservoir. The forward head 37 of the cylinder 36 extendsaway from the outlet end 20a of the assembly and slopes away from silkscreens surfaces operably engaged with the distributor and toward thepiston end of the assembly. The sloping of the head 37 toward the pistonend of the assembly 20 enables the assembly to be positioned with theoutlet end 20a in close proximity to silk screen surfaces 21a withoutthe upper portion of the assembly 20 engaging the frame members 8 orother portions of the printing unit while it is in operation.

As shown in FIG. 11, each assembly further includes a piston 38 disposedwithin the cylinder 36 and adapted to expel printing ink 39 therefrom.In order to prevent the forming of a dead space within the cylinder 36the leading, i.e. ink expelling, face of the piston 38 may be sloped tobe parallel to the head end 37 of the assembly 20 as shown in FIG. 11.

The piston 38 is connected to a piston rod 40, which extends from anactuating piston housed within an actuating cylinder 41. The pistonwithin the cylinder 41 may be pneumatically or hydraulically actuatedunder the influence of conventional control means to provide the desiredbiasing force on the ink expelling piston 38, so as to maintain adesired rate of expulsion of printing ink through a generally elongateoutlet 42 at the leading end 20a of the cylinder 36.

Cylinder 36 is mounted upon a base member 43 by means of threadedfasteners 44 passing through wing portions 45 of the cylinder 36 intothe base member 43. Accurate registration of the cylinder 36 in relationto the base 43 may be secured by a registration key 46, which as shownin FIG. 11, extends into mating and oppositely facing slots in the baseof the cylinder 36 and the upper surface of the base member 43.Actuating cylinder 41 is also rigidly secured to the base member 43 bymeans of a bracket 47.

During certain operating conditions, as for example, when an article ismissing during a printing operation or for purposes of maintenance andadjustment, it may be desirable to retract the assembly 20 away from itsoperative position to the position shown in FIG. 2. For this reason, thebase 43 includes a dove-tail type key 48 integrally formed on the base43, as shown in FIG. 12. Key 48 is slideably positioned within anappropriately configured key way 49 formed .in a stationary base member50. Base member 50 may be intermediately supported by a bracket assembly51 which is attached by the threaded fasteners 52 to the rims 6 and 7.Base 50 may be appropriately elevated on the bracket assembly 51 bymeans of spacers 54. Threaded fasteners 55 are provided for joining thebracket assembly 51, the spacers 54 and the base 50.

Movement of the assembly 20 along the stationary base 50 is effected byan actuating piston and cylinder assembly 56 rigidly mounted upon thebracket 51 as shown in FIG.

I finterior.

12. A piston rod 57 extends from a piston contained within the cylinderof the assembly 56 and is attached at one end:

to the slideable member 43 as shown in FIG. 11. The application of fluidto the piston within the assembly 56 ito :control the extension andretraction of the assembly 20 is controlled by conventional controlmechanisms, not illustrated.

Smooth sliding movement of the assembly 20 may be facilitated byproviding friction easing or resilient packing 58 between the key 48 andthe key way 49 in the general fashion shown in FIG. 12.

In order to facilitate the replenishing of ink within the interior ofthe cylinder 36, the head 37 is made selectviely detachable from thecylinder 36 by means of threaded fastener 37a so that a supply of ink 39contained in a flexible liner 59 may be positioned within the cylinderAs shown in FIG. 11, one end 59a of the liner may be tucked around andsecured to the end of the removable head 37, which lies adjacent theoutlet 42. An- :other end 5% of the liner 59 may be tucked around and:secured to an edge portion 36a of the cylinder 36 which :also liesadjacent the ink outlet 42. The end 5% of the liner may be tuckedbetween a conventional squeeze 60 which is supported on the cylinder 36so as to project beneath the outlet 42 by means of a supporting plate61. As shown in FIG. 11, supporting plate 61 is mounted b tween the base43 and the lower surface of cylinder 36.

A comb-like, ink distributing member 62 is mounted on the cylinder head3750 as to extend across the outlet 42 and control the expulsion of inkfrom the outlet in accordance with varying ink requirements of theprinting pattern along the elongate axis of the outlet 42. Distributor62 is secured to the cylinder head 37 by conventional threaded fasteners63. As shown in FIG. 12, distributor member 62 includes a plurality ofseparately defined, outlets having different sizes conforming to theprinting requirements of appropriate areas of printing patterns on thesilk screens 21a. For example, as shown in FIG. 12, the opening 64 is ofa substantially smaller size than the adjacent opening 65. The differentwidths and depths of openings in the distributor 62 effectively controlthe expulsion of ink in accordance with localized ink demands so as toprevent localized ink accumulations which would occur with uniform inkdistribution where printing patterns have varying ink requirements alongthe axis of the ink outlet 42.

The structural details of the conveyors 3 and 4, including spacedarticle holders carried thereon, are shown in FIGS. 1 and 5 through 10.

Conveyors 3 and 4 are each substantially identical but are disposed inoppositely facing directions as shown in FIG. 1. With this arangementthe lower, horizontal flight 3b of the upper conveyor 3 and the upperhorizontal flight 4a of the lower conveyor 4 travel in the samedirection. As will be appreciated, conventional drive means for theseendless conveyors, not illustrated, effect the driving of the conveyorsat the same linear rate so that the flights 3b and 4a move concurrently.In order to properly correlate the rate of linear movement of theconveyors 3 and 4, it is desirable for these units to be driven by acommon drive mechanism.

As conveyors 3 and 4 are substantially identical, it will be necessaryto describethe structural details of only one conveyor. For this purposeconveyor 4 has been selected.

Conveyor 4 is supported on a pair of upper, horizontally spaced,sprocket wheel assemblies 66 and 67 and a pairf of lower, horizontallyspaced, sprocket wheel assemblies 68 and 69. Upper flight 4a extendsacross sprocket wheel assemblies 66 and 67 while lower horizontal flight4b extends across the lower sprocket wheel assemblies 68 and 69.

Additional support means in the form of an idler roll assembly 70 areprovided. Idler roll assembly 70 is disposed adjacent the printing unit2. Idlerroll assembly 70 is effective tocause theconveyor 4 to traversean arcuate path adjacent the outer periphery of printing unit 2.

As shown in FIG. 5, conveyor 4 includes a conventional, double sprocketchain 71 mounted on one side of the conveyor and another conventional,double sprocket chain 72 mounted on the other side of the conveyor 4. Asis further shown in FIG. 5, each sprocket wheel assembly includes aconventional, double toothed sprocket wheel 73 adapted to meshinglyengage with double sprocket chain 71 and another double toothed sprocketwheel 74 adapted to meshingly engage the double sprocket chain 72. Asillustrated, each double toothed, sprocket wheel is journaled in frameportions of the apparatus. At least one sprocket wheel is provided withdriving means such as the beveled gear arrangement 75 schematicallyillustrated in FIG. 5. Beveled gear 75 is adapted to be actuated by theconventional drive means previously noted.

Double sprocket chains 71 and 72 are interconnected by a plurality ofspaced article holder assemblies. Each such assembly comprises agenerally U-shaped bracket 76 as shown in FIG. 5, which is rigidlyattached at one end 76a to the sprocket chain 71 and is rigidly attachedat the other end 76b to the sprocket chain 72. With this rigid mountingarrangement, it will be appreciated that the bracket 76 is not free topivot relative to the portions of the sprocket chain to which it isattached.

Each bracket member 76 carries an article holding structure. Each suchstructure includes an article cradle 77 mounted on the horizontalportion of the U-shaped bracket 76 as shown in FIG. 5. Each cradle 77includes a generally concave portion 77a as shown in the crosssectionalview of FIG. 6. Concave portion 77a is adapted to support an articleside such that the article is disposed with its longitudinal axisextending horizontally and perpendicular to the conveyor chains 71 and72. An end portion 77b of each cradle 77 provides an abutment forengaging and supporting one article end. The other article end isengaged by a pivoted jaw 78 as shown in FIGS. and 7. Each pivoted jaw'78 is pivotally mounted at pivot axis 79 on the bracket 76 supportingthe cradle 77. A conventional resilient spring 80 is mounted upon thebracket 76 so as to resiliently and yielding urge the pivoted jaw 78 toits article engaging position.

With the article holder arrangement described, positive and accuratesupport for articles is provided so as to insure accurate registrationfor printing purposes. The concave portion 77a of the cradle allows anarticle to naturally assume an orientation so that the surfaces to beprinted face upwardly and downwardly. The abutment 77b, in cooperationwith the pivoted jaw 78 properly position the article along the axis ofthe bracket 76. As is apparent, each article is thus supported with itsmedian plane extending radially from its longitudinal axis to theoutwardly facing surface to be printed and perpendicular to the portionsof the conveyor chains 71 and 72 which it intersects.

The manner in which articles are released from the conveyors and themanner in which article holders are placed in article receiving positionare illustrated in FIGS. 1, 5 and 8.

As shown in FIG. 5, each pivoted jaw 78 carries an enlargement 81 whichfunctions as a cam follower. Enlargement 81 is positioned beneath thebracket 76, as shown.

A cam assembly 82 is provided for simultaneously effecting the pivotingjaws 78 of article holders moving along the upper and lower flights 4aand 4b of the conveyor 4. Cam assembly 82 includes a horizontallyextending abutment bar 83 which provides a cam surface disposed in thetravel path of the followers 81 of pivotable jaws 78 as they move alongthe upper flight 4a. This cam surface comprises the left side of the bar83, as shown in FIG. 5, which side has sloped, camming end portion 830.A bar 84 provides a similar cam surface disposed in the travel path ofjaw followers 81 as the article holders move along the lower flight 4bof the conveyor 4.

Abutment bar 83 is supported upon a toothed rack 85 while abutment bar84 is supported upon a toothed rack 86, as shown in FIG. 1. Toothedracks 85 and 86 extend toward each other and pass slideably through amounting bracket assembly 87. As shown in FIG. 5, bracket 87 is mountedupon a frame portion 88.

Toothed racks 85 and 86 extend in parallel but spaced relationshipthrough the bracket assembly 87 so as to meshingly engage opposite sidesof a pinion 88 journaled Within the bracket assembly 87, in the mannershown in FIG. 8. Pinion gear 88 is mounted upon a rotatable shaft 89 bymeans of which it may be rotated to effect concurrent movement of theabutment bars 83 and 84 toward and away from their respectivelyassociated conveyor flights. This simultaneous adjustment arrangementmaterially facilitates adjusting operations and insures correctpositioning of the camming abutments on both upper and lower flights ofthe conveyor.

If it should become necessary to adjust the apparatus to accommodate toarticles of different sizes, it may be necessary to substitute articleholder assemblies of new dimensions. In this event, the racks 85 and 86may be simultaneously actuated by rotation of pinion gear 88 so as toposition the abutment bars 83 and 84 in accordance with the position ofthe followers 81 in the new assemblies.

The pivoted jaw carried, cam follower and the stationary abutment camarrangement heretofore described provides a particularly reliable butstructurally simple transfer mechanism. As article holders move alongthe upper flight 4a, the cam follower portion 81 of the pivoted jaw 78of each holder engages the camming surface of the abutment 83 so as tocause the jaw 78 to pivot away from solid line article engaging positioninto the phantom line, article receiving, position shown in FIG. 5. Theholders are thus placed in condition to receive articles dropped fromarticle holders carried along the lower flight 3b of the upper conveyor3. Similarly, article carrying holders moving away from the printingunit 2 along the lower flight 4b are caused to discharge articles whichhave been printed on both faces into the conveyor 5 through thecooperation between the camming abutment bar 34 and the followers 81 ofthe pivoted jaws 78 of the article holder assemblies. As will beappreciated, the speed of the conveyor 5 and the positioning of articleholding cradles 5a are so related to the speed of the conveyor 4 and thespacing of the article holding assemblies carried on the conveyor 4 soas to insure the coordinated alignment of the holders carried by theconveyor 4 and the cradles carried by the conveyor 5. In this manner,articles released from the article holding assemblies as they move alongthe lower flight 4b drop freely by gravity into cradles 5 alignedimmediately therebeneath, as shown in FIG. 1.

Conveyor 3 is provided with a somewhat similar article holder actuatingassembly 90 substantially identical to assembly 82 and including anupper camming abutment bar 9011 mounted upon a toothed rack 90!) to liein the path of followers 81 of article holders moving along flight 3a.The mechanism further includes a lower camming abutment bar 90c mountedon a tooth rack 90d and positioned in the travel path of cam followers81 moving along the flight 3b. Assembly 90 is secured to the mechanismframe by a bracket assembly 91 corresponding to assembly 87. A pinion,not shown, is included in assembly 91 to engage racks 90b and 90d toeffect the adjusting of the positions of bars 90a and 900.

As heretofore noted, flights 3b and 4a travel in parallel alignment andat the same linear speed. Article holding assemblies carried on thesetwo conveyors are equally spaced and coordinated in position so that anarticle holder on the lower flight 3b is always aligned with an articleholder on the upper conveyor flight 4a. As will be apparent, articleholder assemblies carried along the flight 3b face downwardly tofacilitate the discharge of articles, while article holding assembliesmoving along the flight 4a face upwardly to facilitate the reception ofarticles dropped by gravity from conveyor flight 3b.

Camming bars 900 and 83 are positioned so as to effect the concurrent orsimultaneous actuation of article holders moving along the flights 3band 4a. In this manner, when a pivoted jaw 78 of an article holdermoving along flight 3b is pivoted out of article engaging position, thepivoted jaw 78 of a holder moving on conveyor flight 4a in alignmentwith the holder moving along the conveyor flight 3b is caused to pivotto an open or article receiving position. In this manner, when anarticle is released from a holder as it moves along the conveyor flight3b, it may drop by gravity into an article holder moving along theflight 4a which has been appropriately disposed to receive the article.

In a manner analogous to that in which abutment bar 83 places holdersmoving along flight 49 in article receiving condition, the abutment bar9% places holders moving along the flight 39 in such a condition. Inthis article receiving condition, holders may receive articles at thetransfer station from any suitable supply mechanism.

As shown in FIG. 1, camming bars 99a and 83 terminate in intermediateportions of their respectively associated flights so as to allow pivotedjaws 78 of the article holders to return to article engaging positionwhile article holders move along the flights 3a and 4a. Thus, articlesreceived by the conveyor flight 4a from the conveyor flight 3b andarticles received by the flight 3a from the transfer mechanism aresecurely positioned and locked in place before moving into inclinedportions of the conveyors. As will be appreciated, the returning of thepivoted jaws 78 to article engaging position completes the registrationof articles to insure their proper positioning to receive indicia.

In certain instances due, for example, to failures in the feedingoperation at the transfer station, a bottle may not be present in anarticle holder being supplied to a printing unit. As will beappreciated, when articles are not present in printing position adjacenta printing unit, the ink supplied to the printing screens will not beutilized, such that an undesired accumulation of ink will result. Inorder to prevent such an accumulation, a missing article controlmechanism may be incorporated with each of the conveyors 3 and 4 of thesystem as shown in FIG. 7. Each such mechanism includes a conventionalmicroswitch having an actuating, pivotable member 92. If an articleshould not be present in an article holder, the pivoted jaw 78 wouldswing to the inclined phantom line position shown in FIG. 7 so as toengage and trip the microswitch member 92 as it moved past this controldevice. The actuation of the switch 92, through means of conventionalcontrol mechanisms, serves to supply actuating fluid to the assembly 56to effect the retraction of the ink distributing assembly 20. Throughthe operation of conventional control means not described, the assembly20 would return to its operable position to effect the printing ofarticles carried by subsequent holders.

FIGS. 1, 9 and 10 illustrate the unique printing unit drive structurefeatured in this invention.

The idler roll assembly 70 of the drive structure includes a framemounted and adjustable idler roll 93 which supports the curving portionof each double sprocket chain adjacent a printing unit. Each idler roll93 is mounted by a conventional roller bearing assembly 94 on a stubaxle 95 extending from a slideable bracket 96. As shown in FIG. 10, eachbracket 96 includes a clamping plate 97 which is secured to a base 98 byconventional threaded fasteners 99. The position of the idler rollsupporting bracket 96 may be adjusted along frame rail portions 100 and101 so as to obtain the proper tautness in the conveyor chains.

As shown in FIG. 10, idler roll 93 lacks sprocket teeth which wouldnormally project into the openings of the sprocket chains such as theillustrated chain 72. Accordingly, the idler roll may be positioned inclose proximity to a printing unit such as the unit 2, so as to causeeach sprocket chain to meshingly engage a sprocket toothed rim carriedby the printing unit 2. As each rim is of the single toothed, ratherthan double toothed variety, each rim would engage only one row ofsprockets in each chain. In the preferred arrangement, the inside row ofsprockets in each. double sprocket chain engages a toothed rim of aprinting unit. As shown in FIG. 9, for example, the sprocket chain 72passes around the periphery of idler roll 93 in meshing and drivingengagement with the toothed sprocket rim 19. As will be appreciated, thechain 71 would similarly meshingly and drivingly engage the toothsprocket rim 18.

As will be appreciated, a printing unit arrangement of the typedescribed exists in connection with the conveyor 4 and the printing unit2 as well as in connection with the first printing unit 1 and the upperconveyor 3.

Each idler roll 93 has a diameter so as to cause its supported endlessconveyor chain to traverse an arcuate path adjacent its associatedprinting unit and cause arcuate article surfaces which are to receiveindicia to move through an arcuate path substantially coplanar withthese surfaces. Idler roll 93 is positioned relative to the travel pathof the curved portions of the silk screen 21a so as to cause articlescarried by the article holders on the conveyors to substantially,tangentially engage the curved portions of the silk screen 21a as thearticles are moved by holders around the idler rollers 93. In thismanner silk screen printing on article surfaces is effected withoutresorting to complex article holder movements which have heretoforeoften been found necessary to achieve tangential indicia forming contactbetween arcuate article surfaces and printing plates.

In the preferred and illustrated embodiment, an article is supported ina cradle 77 so as to permit the outwardly facing article face to beprinted to lie in the same plane as the pitch of the conveyor chain asit passes over the idler rolls 93. As shown in FIG. 2, the silk screenprinting surfaces 21a are supported on the printing units so as to liesubstantially in the same plane as the pitch of the teeth of the toothedrim of the sprocket rims 18 and 19 so as to tangentially engage thearticle faces during the printing operation.

With the intermeshed conveyor and printing drum arrangement the conveyorchain effects the rotation of the printing unit such that the linearspeed of the tangentially engaged portions of printing screens andarticle surfaces to be printed are the same so that conventional, silkscreen printing may be accomplished.

If desired, suitable means not shown may be provided for inflatingarticles such as plastic, blow molded bottles during the printingoperation to provide interior support for the printing surfaces in amanner well-known in the art.

In describing the over-all invention, and the details of operatingcomponents of the various mechanisms, the advantages of the inventionhave been demonstrated. In summary, these advantages include astructurally simple yet highly reliable apparatus for effecting theprinting on two oppositely disposed faces of articles having anoncircular cross-section. A unique rotary printing unit is providedwhich affords continuous access to the unit interior so as to enablemanipulation or adjustment of interior components, such as an inkdistributor, while the printer is in operation. The rotary printer isparticularly characterized by a unique arrangement of printing surfacesand supporting structures where supporting structures extendtangentially away from arcuately curved portions of the printingsurfaces so that an ink distributor contacts only the curved printingsurfaces during the rotation of the printing unit. In this manner, theink distributor contacts only the printing surfaces during the 13rotation of the printing unit, even though the distributor remainsstationary throughout the printing operation.

The ink distributor featured in the invention is unique in that itdistributes ink in accordance with the varyirgg requirements of aprinting pattern and is configured so as to facilitate its dispositionwithin a rotary printing unit so as to allow an ink distributing portionto lie adjacent printing surfaces without the remainder of thedistributor engaging portions of the unit during its rotation.

The article holders featured in the application are characterized bystructural simplicity and yet obtain a uniquely accurate degree ofarticle registration. The holders are particularly adapted for use withthe article transfer mechanism featured in this application, which lacksthe complexity of prior art structures but provides an effectivemechanism for releasing articles from multiple conveyor flights andeffecting the transfer of articles between superposed horizontalflights.

The devices incorporated in the printing mechanism of this invention fordetecting the absence of articles in article holders constitute a uniqueutilization of an article holding component to efiect the actuation ofthe retraction of the ink distributor out of its operable position.

A further characterizing advantage of the invention resides in themanner in which articles are carried on endless chains so as to beimmovable with respect to the portions of the chains to which they areattached, yet effect tangential indicia forming contact between articlescarried thereby and rotating printing surfaces.

Yet another advantage of the invention involves the manner in whichendless conveyors associated with rotatable printing units themselveseffect the rotation of the printing units so as to positively coordinatethe operation of the conveyors with their associated printers.

The invention has been described with reference to preferred embodimentsof the over-all mechanism and its various components. However, thoseskilled in the art may well recognize certain additions, deletions,modifications or substitutions in the disclosed mechanisms which wouldlie well within the purview of the invention as defined in the appendedclaims.

I claim:

1. An indicia forming mechanism comprising:

a pair of interconnected annular rims, said rims being coaxial andspaced along their common axis; means for rotatably supporting saidinterconnected annular rims;

means for rotating said interconnected rims about their common axis;

a plurality of indicia forming plates, each said indicia forming platehaving at least a portion thereof curved in an are having a radiusextending from said comomn axis and having other portions extendingtangentially from the ends of said curved portion;

. support means for said indicia forming plates, said support meansbeing carried by said rims and having portions supporting said otherportions of said indicia forming plates which extend tangentially awayfrom said curved, indicia forming plate portions;

fluid distributing means disposed between said rims and being adapted tobe positioned so as to engage the curved portions of said. indiciaforming plates and, while so positioned, to be spaced from said portionsof said support means which support the tangentially extending portionsof said indicia forming plates as said annular rims are rotated abouttheir coma mon axis.

2. A mechanism as described in claim 1 where at least one of saidannular rims provides a central, circularly shaped aperture to affordaccess to said fluid distributing means while said annular rims arerotating.

3. A mechanism as described in claim 2 wherein said means for supportingsaid annular rims comprises:

' a nonrotatable, annular support member journaled in '14thecentral-aperture of each of said annular rims, ,each said annularsupport member affording access to said fluid distributing means throughthe central aperture of the annular rim supported thereby by Way' of anopening formed in said support member and aligned with said centralaperture.

4. A mechanism as described in claim 1 including means for adjusting theposition of said mechanism transversely of the axis of rotation of saidannular rims, said adjusting means including:

rail means supporting said support members for slideable movementtransverse to said axis;

at least one rack fixed to said annular support member; and

at least one rotatable pinion mounted with its axis stationary inrelation to said support members and in engagement with said rackwhereby, when said pinion is rotated, said mechanism is displacedtransversely of said axis of rotation of said annular rims along thelongitudinal axis of said rack.

5. A mechanism as described in claim 1 wherein said fluid distributingmeans comprises:

a cylinder providing a reservoir of fluid, said cylinder including atone end an elongate outlet facing the travel path of said indiciaforming plates and extending parallel with the common axis of said rims,and a cylinder head, sloping away from said outlet and inclined towardthe other end of said cylinder; and a piston adapted to expel fluidthrough said outlet. 6. A mechanism as described in claim 5 wherein saidpiston has a fluid expelling face parallel to said sloping head of saidcylinder.

7. A mechanism as described in claim 5 wherein said cylinder includes aflexible cylinder liner adapted to contain a supply of fluid, said linerhaving an outlet at said cylinder outlet, with said piston being adaptedto compress said liner to expel fluid therefrom.

8. A mechanism as described in claim 5 and including a fluiddistributing member positioned at said elongate outlet of said cylinder,said distributing member having a plurality of differently sizedopenings adapted to control the expulsion of fluid in response to thedifferent requirements of an indicia pattern along the length of saidoutlet.

9. A mechanism as described in claim 1: wherein each said indiciaforming plate comprises a printing screen, said screen being disposedwith its mid portion curved in said arc and havng its end portonsextending tangentially away therefrom, and

wherein said support means comprises a rectangular screen frame for eachprinting screen, each said frame being disposed with its mid port-ioncurved in said are and having its end portions extending tangentiallyaway therefrom,

said mechanism further including a plurality of holding membersextending between said annular rims, each said holding member includingone slot on one side adapted to receive and retain the extermity of atangentially extending end portion of one frame and a second slot on theother side adapted to receive and retain the extremity of a tangentiallyextending end portion of another frame.

10. An ink distributor for a printing mechanism, said ink distributorcomprising:

a cylinder defining an ink reservoir,

a piston contained within said cylinder and adapted to pressurize inkcontained therewithin;

a cylinder head detachably connected to said cylinder,

squeegee means connected to said cylinder means;

said squeegee means extending transversely past an elongate edge of saidcylinder head in spaced relation therewith so as to define an elongateink outlet communicating with the interior of said cylinder;

an ink distributing member detachably connected to said cylinder headand projecting transversely of, and at least partially across, saidelongate ink outlet, and

a plurality of notches formed on said ink distributing member and havingopen ends generally facing said squeegee means;

at least some of said open ended notches being of different sizes so asto restrict the flow of pressurized ink through said elongate ink outletto differing degrees along said outlet in accordance with differing inkrequirements of a printing pattern.

11. An apparatus as described in claim wherein said cylinder head slopesaway from said elongate ink outlet, generally toward the end of saidcylinder containing said piston, and wherein said piston includes an inkexpelling face which is sloped so as to be generally parallel to saidsloping cylinder head.

12. An apparatus as described in claim 11 including a flexible linercontained within said cylinder and adapted to hold a supply of ink, saidflexible liner having an outlet adjacent said ink distributing memberwith said piston being adapted to compress said liner to effect theexpulsion of ink therefrom.

13. An article handling mechanism comprising:

a plurality of horizontally disposed and superposed,

endless conveyor flights,

at least one article holder carried by each of said flights,

first article holder actuating means associated with one of said flightsand adapted to cause a said holder to release an article so that it mayfall by gravity away from said one flight,

second article holder actuating means associated with another secondflight located beneath said one flight and adapted to actuate an articleholder carried by said other of said flights to place it in an articlereceiving position,

said first article holder actuating means and said second articleholding actuating means being adapted to simultaneously effect thereleasing of an article from a holder carried by said one flight and theplacing of an article holder carried by said other flight in an articlereceiving condition whereby an article released from said one fllightmay fall by gravity into said holder carried by said other flight.

14. An article handling mechanism as described in claim 13 wherein,

each said article holder includes a concave portion for supporting'anarticle side,

an abutment for engaging and supporting one article end, and

a pivoted jaw adapted to resiliently engage and .hold another end ofsaid article, and

said article holder actuating means includes a cam follower carried byeach pivoted jaw, and

abutment means providing cam means disposed in the travel path of saidcam followers and adapted to engage said followers and cause said jawsto pivot away from article engaging position and into article receivingposition.

15. An article handling apparatus comprising:

an endless conveyor having an upper horizontal flight and a lowerhorizontal flight;

a plurality of article holders carried by said endless conveyor, eachsaid holder including a pivotable, article engaging jaw,

article holder actuating means disposed between said upper and lowerconveyor flights, said article holder actuating means including,

a first abutment means providing a cam surface positioned in the travelpath of the pivoted jaws carried by said article holders as they movealong said upper conveyor flight, and

second abutment means providing a cam surface disposed in the travelpath of pivoted jaws of 16 article holders as they are moved along saidlower flight, said cam surfaces each being adapted to engage saidpivoted jaws and pivot said jaws out of article engaging position andinto article receiving position.

16. An apparatus as described in claim 15:

wherein said first abutment is carried by a rack mounted. forreciprocation toward and away from said upper flight,

wherein said second abutment is carried by a rack mounted forreciprocation toward and away from saidlower flight,

said apparatus further including a pinion disposed between and engagingsaid first and second racks and adapted to simultaneously move saidabutments toward or away from said upper and lower flights.

17. A printing mechanism including:

rotatable, indicia forming means;

endless conveyor means for transporting articles toward and away fromsaid indicia forming means;

a plurality of article :holders mounted on said endless conveyor means,each said article holder being rigidly attached to a portion of saidendless conveyor and adapted to support an article such a median planeof the article extending from the longitudinal axis of said articleradially to an arcuate article surface to receive indicia isperpendicular to the portion of said conveyor means which it intersects;

said articles being carried in said holders so that said surfaces toreceive indicia face outwardly;

roller means disposed adjacent said indicia forming means with saidendless conveyor means passing around said roller means;

said roller means having such a diameter as to support said endlessconveyor means to cause it to traverse an arcuate path adjacent saidindicia forming means and cause the arcuate article surface to receiveindicia to move through an arcuate path substantially coplanartherewith;

said roller means and said indicia forming means being positioned so asto cause articles carried by said article holders to substantiallytangentially engage indicia forming surface means of said indiciaforming means as said articles are carried by said holders around saidroller means,

said endless conveyor means being moved at a speed related to the rateof rotation of said indicia forming means so as to cause the surfaces ofarticles to receive indicia traveling around said roller means to moveat the same linear rate as the indicia forming surface means with whichthey are engaged.

18. An apparatus as described in claim 17 wherein said endless conveyormeans engages the periphery of said rotatable indicia forming means toeffect the rotation thereof.

19. An apparatus as described in claim 18 wherein said endless conveyormeans comprises sprocket chain means and wherein said sprocket chainmeans meshingly engages sprocket teeth means formed on the periphery ofsaid indicia forming means.

20. A printing mechanism as described in claim 19 wherein said indiciaforming surface means comprises a plurality of silk screen printingsurfaces.

21. A screen printing mechanism comprising: a pair of interconnectedannular rims, said rims, being coaxial and spaced along their commonaxis;

means for rotatably supporting said interconnected annular rimsincluding a nonrotatable, annular support member journaled in a centralcircular aperture of each of said annular rims;

means for rotating said interconnected rims about their common axis;

a plurality of printing plates, each comprising a printing screen, eachsaid. screen being disposed with its mid- 17 portion curved in an arehaving a radius extending from said common axis and having its endportions extending tangentially away therefrom;

support means for each of said printing plates, each said support meanscomprising a rectangular screen frame, each said frame being disposedwith its mid-portion curved in said are and having its end portionsextending tangentially away therefrom;

ink distributing means positioned between said rims and being adapted tobe positioned so as to engage the curved portions of said printingscreen and, while so positioned, to be spaced from said tangentiallyextending portions of said screens and said screen frames as the annularrims are rotated about their common axis, said ink distributing meansincluding a cylinder providing a reservoir of ink, said cylinderincluding at one end an elongate outlet facing the travel path of saidscreens and extending parallel with the common axis of said rims, and acylinder head, sloping away from said outlet and inclined toward theother end of said cylinder; and a piston adapted to expel ink throughsaid outlet; each said annular support member affording access to saidink distributing member through the central aperture of the annular rimsupported thereby by way of an opening formed in said support member andaligned with said central aperture.

22. An apparatus for consecutively forming indicia on two arcuateportions of an article, said apparatus comprising:

first indicia forming means,

first article conveying means adapted to convey articles toward and awayfrom said first indicia forming means,

second indicia forming means spaced from said first indicia formingmeans,

second article conveying means adapted to convey articles toward andaway from said second indicia forming means,

said first article conveying means having a first portion whereinarticles are transported away from said first indicia forming means,

said second article conveying means having a second portion whereinarticles are transported toward said second indicia forming means, withsaid second portion being disposed beneath and in spaced relation withsaid first portion of said first article conveying means,

means for releasing articles from said first portion which have beenprinted on one arcuate portion so that they may fall by gravity ontosaid second pontion to be carried by said second article conveying meansto said second indicia forming means to receive indicia on a secondarcuate portion.

23. An apparatus as described in claim 22 wherein said first and secondindicia forming means each comprises:

a pair of interconnected annular rims, said rims being coaxial andspaced along their common axis;

means for rotatably supporting said interconnected annular rims;

means for rotating said interconnected rims about their common axis;

a plurality of indicia forming plates, each said indicia forming platehaving at least aportion thereof curved in an arc having a radiusextending from said common axis and having other portions extendingtangentially from the ends of said curved portion;

support means for each of said indicia forming plates, said supportmeans being carried by said rims and having portions supporting saidother portions of said indicia forming plates which extend tangentiallyaway from said curved, indicia forming plate portions;

fluid distributing means disposed between said rims and being adapted tobe positioned so as to engage the curved portions of said indiciaforming plates and, whileso positioned, to be spaced from said portionsof said support means which support the tangentially extending portionsof said indicia forming plates as said annular rims are rotated abouttheir common axis.

24. An apparatus as described in claim 23:

wherein said first and said second article conveying means eachcomprises:

endless conveyor means for transporting articles toward and away fromsaid first and second indicia forming means respectively; and aplurality of article holders mounted on each of said endless conveyormeans, each said article holder being rigidly attached to a portion ofsaid endless conveyor means and adapted to support an article such amedian plane of the article extending from the longitudinal axis of saidarticle radially to an arcuate article surface to receive indicia isperpendicular to the portion of said endless conveyor means which itintersects; said articles being carried in said holders so that saidsurfaces to receive indicia face outwardly; and wherein said apparatusfurther includes roller means disclosed adjacent each said indiciaforming means with each said endless conveyor means passing around saidroller means;

each said roller means having such a diameter as to support a saidendless conveyor means to cause it to traverse an arcuate path adjacentits associated indicia forming means and cause the arcuate articlesurface to receive indicia to move through an arcuate path substantiallycoplanar therewith;

each said roller means and its associated indicia forming means beingpositioned so as to cause articles carried by said article holders tosubstantially tangentially engage said indicia forming plates as saidarticles are carried by said holders around said roller means,

each said endless conveyor means being moved at a speed related to therate of rotation of its associated indicia forming means so as to causethe surfaces of articles to receive indicia traveling around said rollermeans to move at the same linear rate as the indicia forming plates withwhich they are engaged.

25. An apparatus as described in claim 24 wherein said endless conveyormeans comprises sprocket chain means and wherein said sprocket chainmeans meshingly engages sprocket teeth means formed on the periphery ofsaid indicia forming means to effect the rotation thereof.

26. An apparatus as described in claim 25:

wherein each said printing plate comprises a printing screen disposedwith its mid portion curved in said are and having its end portionsextending tangentially away therefrom; and

wherein said support means comprises a rectangular screen frame for eachprinting screen, with each such frame being disposed with its midportion curved in said are and having its end portions extendingtangentially away therefrom.

27. An apparatus as described in claim 26 including means for retractingthe fluid distributing means of each of said indicia forming means awayfrom engagement with the curved portions of the indicia forming platecarried thereby in response to the absence of articles to receiveindicia, said means including:

a pivotable, article holding jaw member adapted to pivot to a particularposition in the absence of an article in a holder,

an actuating member positioned in the travel path of said jaw memberswhen they are pivoted to said particular positions, and

fluid actuated means for effecting the retraction of said fluiddistributing means, said retraction being effected in responsetoengagement between a pivoted jaw member and said actuating member.

References Cited in the file of.=this*patent UNITED STATES PATENTSDeckert Jan. 28, 1896 Brasseur Feb. 24, 1925 Lipton Oct.15, 1946 EllamJuly 20, 1948 Van Buskirk May 13, 1958 Jakob May 13,1958

22. AN APPARATUS FOR CONSECUTIVELY FORMING INDICIA ON TWO ARCUATEPORTIONS OF AN ARTICLE, SAID APPARATUS COMPRISING: FIRST INDICIA FORMINGMEANS, FIRST ARTICLE CONVEYING MEAND ADAPTED TO CONVEY ARTICLES TOWARDAND AWAY FROM SAID FIRST INDICIA FORMING MEANS, SECOND INDICIA FORMINGMEANS SPACED FROM SAID FIRST INDICIA FORMING MEANS, SECOND ARTICLECONVEYING MEANS ADAPTED TO CONVEY ARTICLES TOWARD AND AWAY FROM SAIDSECOND INDICIA FORING MEANS, SAID FIRST ARTICLE CONVEYING MEANS HAVING AFIRST PORTION WHEREIN ARITCLES ARE TRANSPORTED AWAY FROM SAID FIRSTINDICIA FORMING MEANS, SAID SECOND ARTICLE CONVEYING MEANS HAVING ASECOND PORTION WHEREIN ARTICLES ARE TRANSPORTED TOWARD SAID SECONDINDICIA FORMING MEANS, WITH SAID SECOND PORTION BEING DISPOSED BENEATHAND IN SPACED RELATION WITH SAID FIRST PORTION OF SAID FIRST ARTICLECONVEYING MEANS, MEANS FOR RELEASING ARTICLES FROM SAID FIRST PORTIONWHICH HAVE BEEN PRINTED ON ONE ARCUATE PORTION SO THAT THEY MAY FALL BYGRAVITY ONTO SAID SECOND PORTION TO BE CARRIED BY SAID SECOND ARTICLECONVEYING MEANS TO SAID SECOND INDICIA FORMING MEANS TO RECEIVE INDICIAON A SECOND ARCUATE PORTION